On Wednesday Joanne McWilliams, Unite’s industrial officer, said: “Worker representatives in the water group of trade unions agreed to suspend their strike action following an offer made by NI Water management at the end of January.

“In the last weeks, that offer was finally signed off by the finance minister.

“The deal has been endorsed by a large majority of members across all unions.

“The two-year agreement provides pay increases backdated to August 2014 which will more than cover the additional costs associated with pension reform.”

At the peak of the dispute, up to 9,000 properties across Northern Ireland were left without water when staff refused to work overtime or do out-of-hours repairs.

The row centred on NI Water’s bid to roll out public sector pension reforms already implemented in other state organisations.